Re: [PATCH] Subject: [PATCH] x86, AMD: K8 Rev.A-E processors are subject to erratum 400

[Jiri Slaby <jirislaby@gmail.com>]

On 04/29/2011 10:23 PM, Borislav Petkov wrote:
> On Fri, Apr 29, 2011 at 04:11:26PM -0400, Boris Ostrovsky wrote:
>> On 04/29/2011 03:55 PM, Ingo Molnar wrote:
>>>
>>> * Boris Ostrovsky<ostr@amd64.org>  wrote:
>>>
>>>> Signed-off-by: Boris Ostrovsky<Boris.Ostrovsky@amd.com>
>>>> Acked-by: Borislav Petkov<borislav.petkov@amd.com>
>>>> Reported-by: Joerg-Volker Peetz<jvpeetz@web.de>
>>>> Tested-by: Joerg-Volker Peetz<jvpeetz@web.de>
>>>>
>>>> Older AMD K8 processors (Revisions A-E) are affected by erratum 400 (APIC
>>>> timer interrupts don't occur in C states greater than C1). This, for example,
>>>> means that X86_FEATURE_ARAT flag should not be set for these parts.
>>>>
>>>> This addresses regression introduced by commit
>>>> b87cf80af3ba4b4c008b4face3c68d604e1715c6 (x86, AMD: Set ARAT feature on AMD
>>>> processors") so it is somewhat high priority.
>>>
>>> Hm, what is the regression, how do users see it? Hangs? Delays? Crashes?
>>> Something more benign? The changelog should really contain such information.
>>
>>
>> The system becomes unresponsive until an external interrupt (e.g. 
>> keyboard input) happens. The most obvious effect is that time is not 
>> reported correctly. We haven't seen anything worse but that's probably 
>> bad enough.
>>
>> Do you want me to resubmit the patch with updated comments?
> 
> Yes please. Being too verbose is much better than being laconic with the
> commit message.
> 
> Also, please put those lines
> 
> Signed-off-by: Boris Ostrovsky <Boris.Ostrovsky@amd.com>
> Acked-by: Borislav Petkov <borislav.petkov@amd.com>
> Reported-by: Joerg-Volker Peetz <jvpeetz@web.de>
> Tested-by: Joerg-Volker Peetz <jvpeetz@web.de>
> 
> _after_ the commit message.

And also please add
Cc: stable@kernel.org
as the original commit (b87cf80a) was merged into stable trees.

thanks,
-- 
js